SYS ClearImage

Arguments:
                   r4 - *rect 
                   r5 - red
                   r6 - green
                   r7 - blue
Documentation on what this does is... absent at best
formal documentation libraries mysteriously forget that this exists
I suppose the fact that it takes a colour value, I imagine it would... clear a rectangle of the frame buffer with the colour input?
  
00024868: 27bdffd8 addiu r29,r29,0xffd8
0002486c: afb3001c sw r19,0x001c(r29)
00024870: 00809821 addu r19,r4,r0
00024874: 3c048001 lui r4,0x8001
00024878: 248407ec addiu r4,r4,0x07ec
0002487c: afb20018 sw r18,0x0018(r29)
00024880: 00a09021 addu r18,r5,r0
00024884: 02602821 addu r5,r19,r0
00024888: afb10014 sw r17,0x0014(r29)
0002488c: 00c08821 addu r17,r6,r0
00024890: afb00010 sw r16,0x0010(r29)
00024894: afbf0020 sw r31,0x0020(r29)
00024898: 0c0091d0 jal 0x00024740
0002489c: 00e08021 addu r16,r7,r0
000248a0: 02602821 addu r5,r19,r0
000248a4: 321000ff andi r16,r16,0x00ff
000248a8: 00108400 sll r16,r16,0x10
000248ac: 323100ff andi r17,r17,0x00ff
000248b0: 00118a00 sll r17,r17,0x08
000248b4: 02118025 or r16,r16,r17
000248b8: 325200ff andi r18,r18,0x00ff
000248bc: 3c028003 lui r2,0x8003
000248c0: 8c42288c lw r2,0x288c(r2)
000248c4: 34060008 ori r6,r0,0x0008
000248c8: 8c44000c lw r4,0x000c(r2)
000248cc: 8c420008 lw r2,0x0008(r2)
000248d0: 00000000 nop
000248d4: 0040f809 jalr r2,r31
000248d8: 02123825 or r7,r16,r18
000248dc: 8fbf0020 lw r31,0x0020(r29)
000248e0: 8fb3001c lw r19,0x001c(r29)
000248e4: 8fb20018 lw r18,0x0018(r29)
000248e8: 8fb10014 lw r17,0x0014(r29)
000248ec: 8fb00010 lw r16,0x0010(r29)
000248f0: 27bd0028 addiu r29,r29,0x0028
000248f4: 03e00008 jr r31
000248f8: 00000000 nop